## The 131st question in the Extra Practice (PWN 5th edition)

Hi Mike,

So I can’t understand the answer key explanation for the 131st question in the Extra Practice (PWN 5th edition)

Could you explain how to solve this problem?

## A chemist dissolves sodium acetate in boiling water. As the temperature cools down, the crystals start to grow with increasing mass…

m(t₂)−m(t₁)=15(t₂ − t₁ )
A chemist dissolves sodium acetate in boiling water. As the temperature cools down, the crystals start to grow with increasing mass m(t), in grams (g) t seconds (s) after crystallization. The equation above shows this relationship where t₁ < t₂. Which of the following correctly explains the growth of the crystal mass?

The crystal mass grows linearly by 15g per s
The crystal mass grows exponentially by 1g every 15s
The crystal mass grows linearly by a factor 15 every s

## In tennis, a player must win at least 6 games to win a set. If g is the number of games the player won and s is the number of sets the player won, which of the following inequalities must be true?

In tennis, a player must win at least 6 games to win a set. If g is the number of games the player won and s is the number of sets the player won, which of the following inequalities must be true?

A. s ≤ 6g
B. s ≥ 6g
C. 6s ≤ g
D. 6s ≥ g

I thought the answer C and D would cancel out since g is games and number of games is 6. So then I chose A but that answer was wrong. Could you explain the reason for that?

## The polynomial above has zeros at -6 and 2. If the remaining zero is z, then what is the value of -z?

x^3 + 7x^2 − 36

The polynomial above has zeros at -6 and 2. If the remaining zero is z, then what is the value of -z?